CARLTON skipper Marc Murphy remains in doubt for the Blues' crucial clash with North Melbourne at Etihad Stadium on Friday night but Mitch Robinson is set to return.

Robinson (arm) completed a full training session at Visy Park on Thursday morning but Murphy trained away from the main group.

Blues coach Mick Malthouse said he was hopeful Murphy would be passed fit to play despite suffering a twinge in his hamstring in the win over St Kilda last week.

Malthouse said the final decision on Murphy's fitness would be made on game day.

The ninth-placed Blues are a game outside the top eight, percentage clear of West Coast and one game ahead of North Melbourne, Adelaide and the Brisbane Lions. 

Malthouse expects "a very solid test" from the Kangaroos, who he described as a better side than their ladder position indicates.

He said the Blues would have to "reassess" their line-up, particularly in their deployment of Lachie Henderson, given the Kangaroos usually select three tall forwards.

The coach again launched a strong defence of the form of ruckman Matthew Kreuzer, who has been criticised by many experts for not delivering on expectations.

"Has he been beaten badly this year? I don’t know what people carry on about. I've got no interest in it," he said. "Matthew Kreuzer is a fierce competitor… who has got great pride in his performance, very team-orientated, loves Carlton and we love him.

"He's our ruckman and he'll stay here, while I'm here anyway, as the principal ruckman for the organisation."

With Henderson signing a new deal, Eddie Betts reportedly close, and Sam Rowe earning a one-year contract, Malthouse said he would be surprised if any player would want to leave the Carlton given the environment that had been created.

Malthouse wasn't fazed by comments from Geelong coach Chris Scott, who said on Wednesday that Steve Johnson wouldn’t be treated like a "schoolkid" over his one-week suspension.

The Blues fined repeat offender Jarrad Waite earlier in the year after a round-six ban.
 
Malthouse doesn’t believe Scott was taking a swipe at Carlton.
 
"Different circumstances, different clubs… each to their own," he said. "Jarrad will certainly be thinking twice about those trivial things that get him into trouble because he hurt the playing group."
 
Asked about whether he had contacted his troubled former Collingwood charge Harry O'Brien, Malthouse refused to comment, other than to say it was "a private matter".
 
However, he was more forthcoming when paying tribute to fellow Magpie Ben Johnson, who announced his retirement this week.
 
"What an outstanding bloke… one of my all-time favourite players," he said. "Probably represents the Moneyball [philosophy] to an absolute tee. I still remember fighting people over why we should (or) shouldn’t draft him, and he defied all those negatives. Remains one of my dearest player relationships. An absolute beauty."